"Extrude poly ribbon" (ctrl+click) not working for me
Mac: If the answers above don't work for you, try: &#9096; Ctrl&#8984; Cmd LMB

In order for &#9096; Ctrl&#8984; Cmd LMB to work, you must have "Emulate 3 Button Mouse" checked.

To do this: File > User Preferences > Input tab > check Emulate 3 Button Mouse box